Biology
The figures (A) and (B) given below are showing some kind of adjustment. Study the figures and answer the questions that follow.
(a) Identify the kinds of adjustments done in the figure (A) and (B).
(b) Distinguish between the adjustments of figures (A) and (B) on the basis of :
(i) The size of pupil.
(ii) The pigment which gets regenerated.
(iii) Cells of the retina.
Answer
(a) Kinds of adjustments done in the figure:
(A) → dilated pupil due to dim light.
(B) → Constricted pupil due to bright light.
(b)
| S. No. | Factor | A | B |
|---|---|---|---|
| (i) | The size of pupil | bigger | smaller |
| (ii) | The pigment which gets regenerated | Rhodopsin (visual purple) | Iodopsin. |
| (iii) | Cells of the retina | Rods become active and cones become inactive | Cones become active and rods become inactive |
Related Questions
With reference to human eye and ear answer the questions that follow :
(a) Name the parts of the eye associated with:
(i) Regulation of the size of pupil.
(ii) Regulation of the shape of lens.
(iii) Keeping the lens moist and protecting it from physical shock.
(iv) The layer providing nourishment to the eye.
(b) Name the part of the ear associated with :
(i) Static balance.
(ii) Dynamic balance.
(iii) Hearing.
(iv) Amplification of vibrations.
Given below is a diagram depicting a defect of the human eye? Study the same and answer the questions that follow:
(a) Name the defect shown in the diagram.
(b) Give two possible reasons for this defect.
(c) Name the parts labelled 1 to 4.
(d) Name the type of lens used to correct this eye defect.
(e) Draw a labelled diagram to show how the above mentioned defect is rectified using the lens named above.
(a) Draw a neat and well labelled diagram of the membranous labyrinth found in the inner ear.
(b) Based on the diagram drawn above in (a), give a suitable term for each of the following descriptions:
(i) The structure responsible for hearing.
(ii) The sensory cells that help in hearing.
(iii) The membrane-covered opening that connects the middle ear to inner ear.
(iv) The nerves that carry impulses from the ear to the brain.
(v) The tube which equalises the air pressure on either side of the ear drum.
The figure given below refers to the vertical section of the eye of a mammal. Study the figure carefully and answer the following questions.
(a) Label the guidelines shown as 1 to 10.
(b) Write one important role of parts shown as 3 and 7.
(c) Write one structural difference between the parts shown as 9 and 10.
(d) Mention one functional difference between the parts shown as 6 and 8.